Head-mounted displays (HMDs), which also include Helmet-mounted displays are, inter alia, employed for conveying information to a user controlling a vehicle and/or for monitoring parameters relating to the vehicle's operation. HMDs can be configured to display a computer-generated symbol while at same time allowing the user to see through the HMD's visor. Exemplarily, HMDs can facilitate the piloting of an aircraft by displaying to the user (also: pilot) a variety of information including, for example, the aircraft's pitch (also: elevation), yaw (also: azimuth), roll, velocity relative to ground, height and drift.
Under certain circumstances, the user's ability to control a vehicle may become compromised due to sensory mismatch between the sensations felt in the inner ear vestibular system and those experienced through other senses, such as the user's visual perceptions. Examples of sensory mismatch include motion sickness and spatial disorientation such as vertigo.
The description above is presented as a general overview of related art in this field and should not be construed as an admission that any of the information it contains constitutes prior art against the present patent application.